Methods of forming dual-damascene metal interconnect structures frequently utilize relatively low-k dielectric materials to separate layers of metallization from each other and thereby lower parasitic inter-metal capacitance between overlapping metallization patterns, enhance operating speed of integrated circuits and suppress inter-metal crosstalk, for example. Unfortunately, low-k dielectric materials that are formed using organic polymers may be susceptible to damage during selective etching and other related processing steps. For example, some conventional low-k dielectric materials may be susceptible to plasma ashing damage caused when photoresist masks are removed. Some damascene process techniques have been developed to limit ashing damage to organic polymers that may be used as low-k dielectric materials. One such technique, which is illustrated by FIGS. 2A-2J of U.S. Pat. No. 6,911,397 to Jun et al., utilizes a dual hard mask layer to form an interconnection groove pattern within lower and upper insulating layers. Unfortunately, this damascene process technique is relatively complicated and may result in misalignment errors and/or the formation of undesirable photoresist tails. Thus, notwithstanding efforts to limit ashing damage to low-k dielectric materials, there continues to be a need for less complicated damascene process techniques that reduce a likelihood of ashing damage and misalignment errors.